Apparatus for separating solids from a liquid body



A. w. WAY

Feb. 19, 1952 APPARATUS FOR VSEPARATING SOLIDS FROM A LIQUID BODY Filed May 7, 1946 6 Sheets-Sheet l INlNw INN wxw INNLN I N VEN TOR: AmlfnwfzWay, @dal M ATTORNEYS.

Feb, lg), 1952 A, W, WAY 2,586,447

APPARATUS FOR SEPARATING SOLIDS FROM A LIQUID BODY Filed May 7, 1946 6 Sheets-Sheet 2 Z 155 E affff 7@ 7j 7f3 7X /71 Il O o D UK C s E 5l A TTORNE YS.

@zma BY Owl @mi Feb. 19, 1952 A, W, WAY 2,586,447

APPARATUS FOR SEFARATING SOLIDS FROM A LIQUID BODY Filed May 7, 1946 6 Sheets-Sheet 3 ZZ/6 7. 11g ]'G Y 1 v .95 9@ .95 .95 97 M AM FAA AM N 117 l l, #lf

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A. W. WAY

Feb. 19, 1952 APPARATUS FOR SEPARATING SOLIDS FROM A LIQUID BODY 6 Sheets-Sheet 4 Filed May '7, 1946 INVENTOR: /e/z WwW/7 Way, By @a1/LL( /z/w( ATTORNEYS.

A. w. WAY 2,586,447

APPARATUS FOR SEPARATING SOLIDS FROM A LIQUID BODY 6 Sheets-Sheet 5 Feb. 19, 1952 Filed May 7, 1946 v IN1/11N roR.

/e/z WwW/2 Way,

ATTORNEYS.

vv 1 z z 1 lmmnllll 000 Feb. 19, 1952 A. W. WAY

APPARATUS FOR SEPARATING SOLIDS FROM A LIQUID BODY Filed May 7, 1946 WI'I`NESSES 6 Sheets-Sheet 6 INVENTOR: be/z M11/'m Way,

ATTORNEYS.

Patented Feb. 19, 1952 APPARATUS FOR SEPARATING SOLIDS FROM A LIQUID BODY Alben Warren Way, Philadelphia, Pa.

Application May 7, 1946, Serial No. 667,937

This invention relates to apparatus for separating solids from a liquid body and is especially useful in its application to the removal of solid matter from flowing streams of water. In a previously filed application for Letters Patent, Serial No. 624,144, filed October 24, 1945, in the name of John William Morton and myself, there is disclosed and claimed a process of thickening concentrate derived from a solids-laden stream, and apparatus for carrying out the process. The present invention constitutes an improvement which pertains to the same eld of invention, and in its broader aspects has useful application not only to the removal of solids from a natural solids-laden stream, but also from industrial plant waste discharge, from mine discharge, from dredge discharge and from various other sources.

Where the solids content of a owing stream, for example, coal, silt, fines, or the refuse of industrial plant discharge is fairly constant, or

6 Claims. (Cl. 21o-43) varies within a narrow range, it is desirable to employ a process of separation using a time cycle, either for automatic control or as a guide towards efficient manual control, so that the various operations involved may take place in proper sequence and at proper intervals predetermined according to the percentage of solids to liquid, or the range within which such percentage may vary.

On the other hand, where the solids content of a stream, or other source, varies greatly, it is de"- sirable to emploi7 a process using a test cycle in which frequent tests are performed to determine density, and the successive operations of the separating apparatus are gauged or timed according to the fluctuations in density which are periodically encountered.

Accordingly the object of the present invention is to provide apparatus which will meet the problems involved under either of the conditions mentioned above. More specifically, in the apparatus of this invention provision is made for effecting a series of mechanical movements to admit batches of a solids-laden liquid body to a thickening chamber wherein a concentrate is 'formed by gradual accretion of solids, to discharge such concentrate from the thickening chamber in successive batches, and to permit the outflow of liquid, substantially free of solids from said chamber, with such movements performed in the desired sequence and properly timed so as to maintain maximum efficiency and maximum production of concentrate.

In a variant form of the invention provision is also made for periodic testing of the density of the concentrate in the thickening chamber and for discharging each batch of concentrate when it has acquired a predetermined density.

v The invention further comprehends various appliances which make possible a fully auto- 2 matic control of all of the above mentioned me chanical movements involved in the separation process.

Other more specific objects and advantages characteristic of the present invention are set forth more fully in the description of certain practical embodiments of the invention which follows hereinafter and has reference to the accompanying drawings, whereof:

Fig. 1 is a vertical cross-sectional View of a thickening chamber and accompanying parts suitable for the practice of the invention according to the time cycle principle;

Fig. 2 is a rear elevation of a series of such thickening chambers, partly in section, as indicated by the arrows II-II in Fig. 1;

Fig. 3 is a diagrammatic representation of the timing mechamsm and other apparatus used for remotely and automatically controlling the mechanical movements performed at each separating chamber; Y

Fig. 4 shows the motor and associated speed reducer and regulator for driving the timing mechanism;

Fig. 5 shows in detail, partly in elevation and partly in section, the apparatus for controlling vertical motion of each back washing nozzle;

Fig. 6 shows in detail the apparatus for controlling the supply of water to each back washing nozzle;

Figs. 7 and 8 show in cross section and in side elevation, partly in section, details of one of the timing devices shown in Fig. 3;

Fig. 9 is a vertical cross-sectional view of a portion of a thickening chamber and accompanying parts suitable for the practice of the invention according to the test cycle principle;

Fig. 10 shows in enlarged detail and in cross section the test tube, density testing chamber, and associated mechanism;

Fig. 11 is a view somewhat similar to Fig. 10 but shows the valves of the test tube in diierent positions;

Fig. l2 is a cross-sectional view of the same taken as indicated by the arrows XLI-XII of Fig. 10;

Fig. 13 is a View of an electrically and pressure operated valve associated with the density testing apparatus;

Fig. 14 is a diagrammatic representation of the timing mechanism and other apparatus for remotely and automatically controlling the mechanical movements at each chamber according to the test cycle principle; and

Fig. 15 shows in detail a pressure operated cam for controlling each of the manifolds shown in Fig. 14.

In the accompanying drawings, with special reference to Figs. 1 and 2, a body of solids-laden Water is shown at I. It may be assumed that the body of water is derived from a natural stream, or is discharged from an industrial plant, vor comes from any other source. A thickening chamber is represented at 2. The solids-laden water enters the chamber 2 through an opening 3 in the region of its upper end, and discharges substantially free of solids through a screen II located near the bottom of the chamber, Admission of water into the chamber 2 is controlled by a gate 4 in the opening 3, which is moved up and down by a rod 5, the reciprocation of which is accomplished by a double piston l24 operated by opposed pressure cylinders 6, Ba controlled remotely and automatically as hereinafter described by pressure lines 5I and 55 which cause the gate 4 to be opened and closed at the proper time and for the desired intervals. As the capacity of the intake gate 4 is greater than that of the screen II, the solidsfladen liquid fills the chamber 2 to approximately the level of water in the entrance channel. To prevent the entrance into the chamber 2 of unduly large solids, a coarse screen 9 guards the inflow of the stream on the outside of the gate.

A frame forthe screen i I is formed at the outlet I of the chamber 2. It may be assumed that the screen I I is so constructed that notwithstanding its neness it is capable of resisting the pressure to which it is subjected. A protecting screen I2 of relatively coarse m esh is disposed at the inside of the settling chamber to prevent large solids from being carried against the. fine screen II. At its base the chamber. 2 is desirably in the shape of a funnel forming a sump I having an exit H3 along its bottoni controlled by a valve I'I, the opening and closing of which is. accomplished by opposed pressure cylinders I8, Ia having a double piston 22 attached to an endless chain I9, trained around idle sprockets 2| and also around a sprocket 2D which operates the valve I'I. The pressure. cylinders I8, I8a are operated automatically and by remote control, as hereinafter described, by pressure lines 5,2 and 54.

A baffle plate 25 is mounted more or less centrally in the thickening chamber 2. It extends downwardly far enough to prevent direct impact of the incoming stream against the filtering means at the outlet i0, and causes the flow to take a general horizontal direction as it approaches the outlet. On the outside of the outlet I8 there is a nozzle. 30 extending across the width of the. screen II and capablev of projecting a iet of water under4 considerable pressure against the screen from the, outside, the purpose of the jet being to keep the inner surface and meshes of the screen. clean by forcing therefrom any accumulation of solid matter which may tend to clog the screen. The nozzle 3i] is fixed on a framelike structure 3l guided for up and down movement by guides 32 on the rear wall of the chamber 2 and reciprocated by a crank disk 34 with which the structure 3l is connected by a rod 3.3. The shaft 21 of the crank disk 34 has a Worm gear 35 driven by a worm 35 on a shaft 3l. The shaft 3l is operated by a motor 38 through reduction gearing 39 located upon the working platform 29,.

Each nozzle 30 is supplied by a water line 40 from which proceed branches, each having a ilexible or extensible component 4I and a spreading end 42. Flow of water under pressure through the` nozzles 30A is controlled remotely and automatically by mechanism which is hereinafter described.

Below the valve II which controls the bottom outlet I6 an elongated conduit 44 is provided Withl in which operates a screw conveyor which by continual rotation carries with it to a desired point or discharge all of the concentrate produced in and removed from the thickened chamber 2.

'Ehe description thus far has been directed to a single thickening chamber, but it is to be understood that it is generally desirable to provide a Series of separate chambers placed in juxtaposition to each other and having their inlets and outlets at a common level. Mechanism for performing the various operations for opening and closing the intake gate 4, for effecting the vertical movement of the nozzles 30, for controlling the jet of water from the nozzles 3U, and for opening and closing the valve Il is duplicated at each chamber in the series.

As shown in Fig. 3 the means for controlling the various operations at each chamber 2 in the illustrated example of the invention constitute a number of pressure lines to 55 leading to each instrumentality at the particular chamber the operation of which is to be controlled, the ilow of pressure fluid at each chamber being governed by a corresponding number of shut-off valves 56 to G l.

Pressure lines 5I and 55 lead to the cylinders 5 and 5a respectively and control reciprocation of the double piston 24, shown in Figs. 1 and 2, which is connected to the rod 5 and which nieves the intake gate 4 to open orclosed position, depending upon whetherpressure is applied to cylinder 6 or cylinder 6a.

Pressure lines 52 and 54 lead to the cylinders I8 and ISa respectively and control reciprocation of the double piston 22 shown in Fig. 1, which is connected to the endless chain I9 and which causes the discharge valve I1 to. be opened, or closed, depending upon whether pressure is applied to cylinder I8 or cylinder [8a.

Pressure lines 59 and 53 lead to cylinders 6'3 and 53a respectively, shown in Fig. 6, and control movement of a yoke (55 connected to piston E6 and 6lmoving in cylinders 6;3 and 63a. The yoke B5 is in turn connected to a valve rod 58 which operates the gate (i9` of a cut-off valve 10 controlling the supply of water to the hose 4I and thence to each nozzle 30.

In practice it is desirable to add to the control devices mentioned above certain safety features to insure against various failures or improper operation of the valves associated with the chamber 2 but such safety features form no part of the present invention and hence are not shown.

With further reference to Fig. 3, the shut-.off valves 56 to 6I are simultaneously operated by means of a connecting rod II having links I2 leading to each such valve. It will be understood that all of the valves 5B to. 6I are opened or closed together, and that whenever pressure is admitted to one cylinder, such as cylinder 6, its companion cylinder 6a is exhausted. Where air under pressure is used as the pressure medium such exhaust may beto the atmosphere. A springl 'I3 urges movement of the connecting rod II- to the left as viewed in Fig. 3. A piston 'I4- movable within a cylinder 'I5 urges the connecting rod 'H in the opposite direction when pressure is admitted to the cylinder 15- through` pipe 8U-, De! sirably the shut-off valves 56 and 5I are located nearthe chamber the functions of which they control, and in close proximity to each other. They may be situated at the working platform 29. Although only one set of shut-off valves has been shown in the drawings, this set consisting of six valves associated withV one chamber, it will desde@ be understood that a similar set of valves will be provided for each thickening chamber 2 that is employed. Upon the assumption that six chambers constitute a convenient number for a section of a separating plant, six connections are illustrated at 80 to 85, but only the apparatus associated with one connection, that shown at 80. is illustrated in the drawings.

The ow of pressure uid to shut-off valves 56 to 6| through pipes 8B to 9| is controlled by timing valves 92 to 91. Similarly the ow of pressure fluid through pipes 80 to 85 is controlled by timing valves to |05. Each timing valve 92- 91, |00|05 is connected to a source of pressure and has a valve rod |06 governing opening or closure actuated by a cam |01.

One group of six cams |01 is mounted upon a shaft |08 which is caused to revolve at a constant speed, and the other group of six cams is mounted upon an additional shaft |09 connected to shaft |08 by reduction gearing ||0. As shown in Fig. 4 shafts |08, |09 are driven by a constant speed electric motor through a speed change and regulating mechanism ||2, a worm ||3 and a worm gear |4 mounted upon shaft |08. Each cam |01 may take a form such as illustrated in Fig. '1. When the roller ||6, see Figs. '1 and 8, at the lower end of the valve rod |05 engages the raised cylindrical surface of the cam disc |01 the timing valve 92a is maintained in the raised position against valve seat H1 shutting off the flow of pressure fluid from pipe I8, which leads to the source of pressure, to pipe 86. On the other hand, when the roller I6, urged downward by a spring ||9 and guided by sleeves |22, engages the depressed surface |20 of cam |01, valve 92a is withdrawn from valve seat ||1 and valve 92h is lodged against valve seat |2l. Flow is then permitted from pipe ||B to pipe 86. Valve 9217 when raised from its seat |2| permits an exhaust from pipe 85 to the atmosphere through port |23. The set of six cams |01 mounted on shaft |09 is preferably caused to rotate at one-sixth of the speed of rotation of shaft |08, this being accomplished by use of reduction gearing establishing a 6 to 1 ratio between shafts |08 and |09. The shaft |08 and the cams |01 associated therewith are comprehensively designated as timer A and the slower moving shaft |09 and associated cams are designated as timer B. If it be assumed that timer A operates at a speed of one revoultion in five minutes and timer B operates at a speed of one revolution in thirty minutes, it will be apparent that the cams may be so constructed and arranged with respect to each other that the sequence of operations at each chamber may be staggered at five minute intervals so that when any one chamber is discharging its concentrate with its intake gate 4 closed, the ve other chambers of the section will be actively accumulating solids by the thickening process. It will also be apparent that the cams |01 of timer A are so arranged and constructed that when one cylinder of a pair, such as cylinder 6, is under pressure the opposed cylinder 6a will exhaust to the atmosphere.

CII

6 freely upon the shaft 21. The clutch |25 is normally disengaged and held out of action by a spring |29 bearing against a collar |30 keyed to shaft 21, but when water is turned on at the nozzle 30 pressure from line 50, which is the control line governing water supply to the nozzle, is admitted to a cylinder I3|. Shaft 21 has an enlarged end |32 tting within cylinder |3| and serving as a piston. Accordingly under the influence of pressure Within the cylinder |3| shaft 21 moves to the right, as viewed in Fig. 5, causing clutch element |28 to engage clutch face |28 so that shaft 21 is caused to rotate. When pressure in the cylinder I3! is relieved the clutch |25 will be disengaged under the inuence of spring |29 and rotary movement of the crank disc 34 will cease.

In the second form of my invention illustrated in Figs. 9 to 15 there is shown apparatus designed to meet the special problems involved where the supply of solids-laden water varies greatly as to the solids content. Such apparatus I conveniently term test cycle apparatus. In this form of the invention each chamber 2 may be considered to involve all of the apparatus hereinbefore described but to include additionally a test tube |40 fitted into the side of the thickening cup |4| of the chamber in a nearly vertical position, as shown in Fig. 9, with its upper end extending into the cup to a point where it is desirable to secure the material to be tested, which in most cases is Well towards the center of the cup. As depicted in Fig. 10, the tube 40 is carefully tted to the side of the cup |4| and made water tight by a stuffing box |42.

Valve seats |43 and |44 are provided at each end of the tube |40 and the corresponding valves |45 and |46 are mounted on a valve stem |41, which comprises inner and outer concentric tubes |38 and |39 extending throughout the entire length of the test tube |40 and for some distance below its lower end.

To the bottom of the test tube |40 is fitted a casting |48, somewhat in the shape of a smokers pipe, and designed to permit free flow from the test tube 40 into the bowl |49 and from thence into the upright vertical section |50, which constitutes a testing receptacle. A valve |5| is provided at the lower end of casting |48 directly in line with the valves |45 and |46. An overiiow receptacle |52 is formed adjacent to the testing receptacle |50 and is preferably an integral part of the same casting |48. An opening |58 leads from the testing receptacle |50 to the overow receptacle |52. Below the lower valve |5| there is a cylinder |53 operated in its upward motion by pressure fluid supplied from a pipe 2 i3d, and its downward motion by a spring |55. The spring |55 bears against the flange of a collar |55 mounted on the valve stem` |41, and tends to move the stem downwardly. When pressure is admitted at pipe 2|3a it exerts a force upon a piston |54 mounted on the valve stem |41 and moves the stem upwardly.

In operation the valve stem |41 has two positions. When at rest or in its lowered position. see Fig. 10, the valve stem |41 maintains valve |45 closed against its seat |43 and valve I5! closed against its seat |51 whereas valve |46 is open. When a test is made, valve stem |41 is raised by pressure in cylinder |53., opening valves |45 and |5| and closing valve |46, as shown in Fig. 1l. A charge or sample is then admitted from the thickening cup |4| into the test tube |40, such sample consisting of a definite quantity of concentrate. At the same time, valve |5| being opened, any old test material remaining in the bowl |49 is allowed to flow away through discharge ports |59 at the base of casting |48. When pressure is relieved in cylinder |53, the spring |55 pushes valve stem |41 downwardly closing valves |45 and |5| and preventing more material from entering the test tube |40, also opening valve |46 and allowing the sample to ow into bowl |49. The sample fiows upwardly into the testing receptacle |50 filling that receptacle to the level of the opening |58 with any excess overflowing into the overflow receptacle |52, thereby establishing a definite level for the sample being tested.

In order to prevent air locking oi' the test tube 40 Vents |90, |98 are provided leading from the interior of the test tube |40 `to the annular space |31 between the concentric tubes |38, |39. One such vent |90 consisting of a number' of ports is disposed at the upper end of the 'tubular stem |41.

When the tubular stem |41 is in its raised position valve |45 slides downwardly on the stem |41 under the force of a spring |92 which bears against the flanged end of a plug |93 secured within the upper end oi the tubular stem |41. Such movement is sufficient to cover vent |90, but is limited by an abutment |94 formed on the tubular stem |41 immediately beneath vent |90. When the tubular stem |41 is lowered vent |90 is uncovered. Similarly valve |46 has a spring |95 associated therewith bearing against a collar |96 fixed on the tubular stem 41 in such manner vthat in the lowered position of the stem |41 valve |46 engages abutment |91 and covers vent |98, and in the raised position, shown in Fig. 11, upon seating of the valve |46, this vent |98 is uncovered. An additional vent |9| is provided near the top of valve stem |41 and in a position where it is covered and uncovered by movement or' valve |45, this vent |9| leading from the interior of the test tube |40 to the inside of lthe inner tube |38. At the lower end of the innermost tube |38 a flexible hose |36 is attached to the tube to admit water under pressure which is used for periodic cleaning of the test tube |40 by admission through vent |9|.

In the testing receptacle |50 there is a float |69 held in a central position by means of a wire cage |6E. As the sample assumes a fixed position or level, the oat |60 also assumes a fixed position, depending upon the density of the sample being tested.

As shown in Fig. l the fioat |60 has a light rod |62 extending above it and traveling up or down with it while being maintained in a vertical position by a loose tting bearing |63. At `the top of the rod |62 is a washer |64 of insulating material and above it a metal ring |15 insulated `from the rod |62. To the top of casting |48 is hinged at |99 an arm |65 on the front of which is a metal plate |66 insulated from the arm |65 and so located that it lightly touches the metal ring |15 at the top of rod |62. Metal plate |66 is connected electrically to an electric terminal |61. To the top of the opposite side of casting |48 is rmly secured a second casting |68 having an adjustable verticallysliding fixture |69 fitted with a metal plate insulated from the body of the sliding fixture |69. Metal plate |19 is also connected to a second electrical terminal |1|. Adjustment of the vertical position of the sliding fixture |69 with respect to its guiding element |85 is accomplished by a threaded shaft |68 turned by a hand wheel |89. Metal plate |16 is laterally displaced from the metal ring on rod |62 and the position of the bottom edge of 8 plate |10 determines the point to which rod |62 must be raised to effect an electrical contact.

To the hinged arm |65 there is attached a U- shaped arm |12 connected to a piston |14 within a cylinder |13, the piston |14 having a short stroke, the limit of travel being controlled by an adjusting screw 25|) which bears against one end of an arm 25| pivoted at 252 and adapted to strike an abutment 253 on the U-shaped arm |12.

Material from the thickening cup |4| ows into the bowl |49, establishes a level in the testing receptacle |50, and causes the float |60 to come to rest at a fixed level. Pressure `admitted to cylinder |13 draws arm |65 to the left, as viewed in Fig. 10, pressing metal ring |15 at the top of rod |62 towards metal plate |10. The adjustment of the parts is such that the lower end of plate |10 is just low enough relative to stop rod |62 to establish an electrical contact between terminals |61 and |1| when the sample has acquired a predetermined density. By the described construction the float |66 and rod |62 are free to move up arid down without appreciable friction. In order to prevent any excessive 11p-surge of iloat |60 when the sample is first introduced into the testing receptacle |56, a collar |39, adjustable by means of a set screw |34, is mounted on rod |62, and by engagement with bearing |63 limits upward movement of rod |62 under such conditions.

Also mounted on casting |48 is a fixture 255 with three pipes :2|3a, 2|4a and 2|5a carried by it, these pipes leading from a timing device hereinafter described. Pipe 2I3a leads to the cylinder |53 which operates the valve stem |41 in test tube |40. Pipe 2|4a leads to cylinder |13 which operates the swinging arm |65. Pipe 2 |5a leads to a cylinder 256 having a piston 251 connected to a valve rod 258 operating a valve 259. Valve rod 258 and valve 259 are normally maintained in a lowered position by means of a spring 260. A pipe 26| leads from a source of water under pressure to the side of valve chamber 262. When the piston 251 is actuated by admission of a pressure fluid to cylinder 256 valve 259 is raised allowing water under pressure to ilow from pipe 26| to flexible hose |36 leading to the inside of the inner tube |38 of valve stem |41. At the start of each new test a charge of clear water is admitted to the test tube |40 through vent |9| to wash the tube as well as the bowl |49 and testing receptacle |50.

The effect of making a contact between terminals |61 and |1| is to energize a magnet |16, see Fig. 13, through wires |11 and |18, drawing a rod |19 to the right, as viewed in Fig. 13, and throwing the vertical arms of a toggle |8| oi center allowing a spring |82 acting upon a valve rod |15 to open a valve |83 in chamber |84 so that impulses derived from a timing device herenafter described cause a flow of pressure huid through pipe 2I2a and set in motion a sequence of operations at the chamber under test commencing with the discharge of concentrate therefrom. At the proper point pressure impulses admitted to a cylinder |86 cause a movement of piston |81 connected to rod |19 forcing the rod |19 to the left and closing valve |83 by resetting the arms |89 of toggle |8I. An adjusting screw |35 regulates the stroke of piston |81. When the toggle |8| has been reset and the parts are in the position represented in Fig. 13 further impulses admitted at cylinder |86 will have no effect upon valve |83. Such impulses will only cause a' movement of piston |81 after magnet |16 has been energized.

In Fig. 14 the timing devices for control by test cycle are illustrated. Timer C may be assumed to be in all respects similar to timer A of the time cycle control mechanism previously described. Timer D may also be assumed to be similar to timer B previously described except that it is driven at the same speed as timer C and comprehends only five cams in this particular example of the invention. Timer C and D are driven by a motor 200 through a speed reducer and regulator 20|.

Pipes 202 to 201 lead from the timing valves of timer C past all the separating chambers of the plant with branches 202a to 201a to each chamber 2 which perform the same functions in the same manner as the pipes 86 to 9| previously described in connection with timer A except each branch pipe 202a to 201er leads through a manifold 209 and thence to cylinders 6, 6a, |8, |8a, 63 and 63a, such manifold 209 being controlled by a single cylindrical cam v2|0 and associated mechanism as shown in detail in Fig. 15. The source of pressure fluid to timers C and D is a pipe indicated at 208.

Pipes 2|| to 2|5 lead from the timing valves of timer D past all of the separating chambers of the plant with branches 2||a to 2|5a to each chamber. More specifically, pipe 2||a leads to one end of a cylinder 2|6, shown in Fig. 15, and governs the opening of the series of valves in manifold 209 whereas pipe 2|2a leads to the other end of cylinder 2|6 and under certain conditions governs closure of manifold 209. The piston 220 within cylinder 2|6 is connected by a rod 22| with a link 222 attached to a cylindrical cam 2|0. Cam 2|0 engages rollers 224 on the lower ends of valve rods 225 and simultaneously operates the entire series of valves 226 within manifold 209. Each valve rod 225 is urged downwardly by a spring 221 and is guided within bearings 228. In an obvious manner when the rollers 224 engage the depressed surface 229 of cam 210 all of the six valves 226 within manifold 209 will be caused to open simultaneously permitting ow through pipes 202m to 201a to pipes 20219 to 201|) which lead to cylinders 6, 6a, I8, |8a, 63, 63a and control the mechanical movements of the intake gate 4, the discharge valve |1 and the back washing nozzles 30, as well as the supply of water to the nozzles 30, all as previously described.

With further reference to the pipes 2|| to 2`|5 leading from timer D it will be noted that branch pipe 2| la has a branch 2| |-b which leads to cylinder |86 whereas branch pipe 2|2a leads through chamber |84 and its valve |83 (Fig. 13). Branch pipes 2|3a, 2| 4a and 2|5a lead to the density testing apparatus as previously described.

Desirably the manifolds 209 and mechanism illustrated in Fig. are located at the level of the working platform 29 above the chambers 2, and hence pipes 2I| and 2|2 are run from the control stationA where timer D is located to the overhead platform of the separating plant, with their branches 2| la to 2|2a leading to positions above each chamber of the plant. On the other hand pipes 2|3, 2|4 and 2|5 are preferably disposed at a lower level beneath the chambers 2 with their branches 2|3a to 2|5a leading directt ly to the density testing apparatus at each chamber.

Operation of the density testing apparatus is as follows. Upon the assumption that the valves 10 |45 and |5| are open and that valve |46 is closed spring |95 is compressed and vent |90 is uncovered releasing any back pressure or air locked in the test tube |40. Trapped air will flow out through vent |90 and the annular space |31 between concentric tubes |38 and |39 to the atmosphere. Upon the next actuation of valve Stem |41 with the closing of valves |45 and |5| and the opening of valve |46 the sample in the test tube |40 will flow downwardly through valve |46 and around into the testing receptacle |50. Air will then flow into the upper part of the test tube |40 through vent |90 again preventing an air lock. After a test of the sample has been made in the testing receptacle |50, valve 259 will be opened and clear water delivered through exible hose |36 into the inner tube |38 and from thence through vent |90 into the body of test tube |40. Prior to the next test with the raising of valve stem |41 valve |5| will be opened emptying all old material from the previous test, as well as washing water, through the ports |59 at the base of casting |48.

At any chamber 2 of the plant during the period while the concentrate forming in the thickening cup |4| has not reached a suiiicient density so that tests of samples produce electrical contact between terminals |61 and |1| of the density testing apparatus the magnet |16, shown in Fig. 13, will be de-energized and the valve |83 will be held closed by spring |82. Under these conditions there can be no ow of pressure fluid to manifold 209 through pipe 2|2a and all of the Ivalves 226 of the manifold will be held closed so that impulses received at manifold 209 from timer C will have no effect with the result that the separating process will continue at the chamber from which such tests have been made with negative results. On the other hand, when the density of the sample concentrate reaches a predetermined value and a positive result is obtained establishing an electrical contact between terminals |61 and |1|, magnet |16 will be energized and valve |83 will be opened. Under these conditions impulses received at manifold 209 through pipe 2 |2a will cause all of the valves 226 of that manifold to open, and thereafter under the influence of impulses from timer C the intake gate 4 will be closed, discharge valve l1 will be opened and the movement of nozzles 30, as well as the supply of water thereto, suspended. After the discharge of concentrate from the chamber 2 through valve |1, the testing receptacle having been emptied of its contents, contact between terminals |61 and |1| will be broken and magnet |16 de-energized. The next impulse received in cylinder |86 through pipe 2||a will cause the toggle 8| to be reset and valve |83 to be closed.

' The impulse from pipe 2| la will also close all of the valves 226 of manifold 209 so that the cycle is ready to be repeated.

While I have described my invention in considerable detail showing two specific embodiments and the particular mechanism for controlling all of the operations at a separating chamber, it will be apparent that numerous changes may be made in the form of the apparatus herein described and illustrated, and that certain features of the invention may at times be used to advantage without a corresponding use of other features, all without departing from the spirit of the invention as defined in the annexed claims. It should also be understood that although the apparatus of this invention is referred to as apparatus for separating solids from a liquid,

I do not wish to imply that the concentrate as discharged from the thickening chamber is free of liquid, but rather that the ratio of liquids to solids therein has been reduced to the point where the solid matter is readily recoverable.

Having thus described my invention, I claim: 1. In apparatus :for separating solids from a liquid, including a screened retention chamber having a region wherein a substantially homogeneous concentrate is formed by gradual accumulation of said finely divided solids, said chamber having an outlet opening for the discharge of screened liquid and also having another outlet opening for said homogeneous concentrate, a conduit penetrating said chamber having means for eiecting periodic withdrawals of samples of the concentrate from said region of said chamber to an exterior fluid receptacle, testing means in said receptacle for testing the density of the samples thus withdrawn, and iiow controlling means connected to the concentrate outlet opening and responsive to the action of the density testing means for opening the concentrate outlet opening and thereby automatically discharging the entire content oi the chamber when the concentrate therein has acquired a predetermined density.

2. In apparatus for separating solids from a liquid, a screened retention chamber having a region wherein substantially homogeneous concentrate is formed by gradual accumulation of said finely divided solids, said chamber having a liquid inlet opening and also having an outlet opening for the discharge of screened liquid,y

another outlet opening for said concentrate, a sampling conduit penetrating said chamber having means for effecting periodic withdrawals of concentrate samples from said region of said chamber to an exterior receptacle, float means in said receptacle for testing the density of the samples thus withdrawn, and flow controlling means connected to the concentrate outlet opening and liquid inlet opening and responsive to the density testing means for automatically discharging the entire content of said chamber and subsequently admitting a second batch of solidsladen liquid when the concentrate therein has acquired a predetermined density.

3. In apparatus for separating solids from a liquid including a chamber wherein a concentrate is formed by gradual accretion of solids and having a concentrate discharge conduit and a screened outlet for discharge of liquid, a sample conduit penetrating said chamber, timer-actuated valve means opening and closing said sample conduit for effecting periodic withdrawals of samples of the concentrate, each of a measured quantity, from said chamber to an exterior receptacle, noat means in said receptacle for measuring the density of the sample, and iiow controlling means for opening and closing the concentrate discharge conduit, said iiow controlling means being actuated in response to the movement of the float means and effective to discharge the concentrate from said chamber when it has acquired a predetermined density.

4. In apparatus for separating solids from a liquid including a chamber wherein a concentrate is formed by gradual accretion of solids, said chamber having an inlet, a concentrate discharge conduit and a screened outlet for discharge of liquid, a sample conduit penetrating said chamber, valve means in said conduit for eiecting periodic withdrawal of concentrate samples from said chamber, a timing device operatively connected to said valve means for controlling the periodic movement thereof, a test receptacle for the samples thus withdrawn, float means in said test receptacle for measuring the densities of the samples, mechanical means for opening and closing 01T the concentrate discharge conduit, and an electric circuit including a switch having a contact movable in response to the movement of said lioat means to make and break the circuit, said circuit also being operatively connected to said mechanical means and effective for opening and closing the concentrate discharge conduit in response to the movement of said oat means.

5. In apparatus for separating iinely devided solids from a liquid body including a chamber into which the solids-laden liquid is admitted in successive batches and wherein a concentrate is formed by accretion of solids, said chamber having a screened outlet for discharge of clear liquid, density testing apparatus including a conduit having means for withdrawing samples from the chamber at regular timed intervals and a receptacle having float means for determining the density of the samples withdrawn, mechanical flow interrupting devices coacting with the density testing apparatus for automatically shutting off the admission of liquid into the chamber and discharging the concentrate therefrom when a test of the sample indicates that its density has reached a specic Value, and for continued operation independently of the action of the iloat means when a test of a sample indicates that its density is below said specific value.

6. In apparatus for separating iinely divided solids from a liquid body including a series of chambers into which the solids-laden liquid is admitted in successive batches and wherein a substantially homogeneous concentrate is formed by accretion of solids, said chambers having screened outlets for discharge of liquid, iioat means for independently testing the density of samples of the concentrate from each individual chamber of the series, and valve means operatively connected to said iloat means for automatically and independently shutting oil the admission of liquid into any chamber and discharging the concentrate therefrom when a test of a sample therefrom indicates that its density has reached a specific denite value.

ALBEN WARREN WAY.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date Re. 21,741 Samiran Mar. 4, 1941 368,544 Morrison Aug. 16, 1887 952,620 Keyes Mar. 22, 1910 1,071,784 Nutter Sept. 2, 1913 1,140,131 Dorr May 18l 1915 1,454,756 Mennell May 8, 1923 1,471,342 Logan Oct. 23, 1923 1,530,836 Kuzilik Mar. 24, 1925 1,908,691 Coe May 16, 1933 1,957,898 Mitchell May 8, 1934 1,979,169 Mitchell Oct. 30, 1934 2,295,366 Stout Sept. 8, 1942 2,317,847 Duden Apr. 27, 1943 2,324,637 Moor July 20, 196.13 2,454,653 Kamp Nov. 23, 1948 

